Stackable containers

ABSTRACT

A STACKABLE CONTAINER COMPRISING A BOTTOM, A SIDEWALL INTEGRAL WITH SAID BOOM TAPERING UPWARDLY AND OUTWARDLY FROM SAID BOTTOM AND TERMINATING IN AN OPEN UPPER END, A FIRST CIRCUMFERENTIAL INTERMITTENT SHOULDER IN THE CONTAINER SIDEWALL, AND A SECOND CIRCUMFERENTIAL INTERMITTENT SHOULDER IN THE CONTAINER SIDEWALL, AT LEAST ONE OF SAID SHOULDERS BEING FORMED BY SPACED PROJECTIONS NO PART OF WHICH SLOPE INWARDLY TOWARD THE CENTRAL AXIS OF THE CONTAINER, THE OTHER SHOULDER MAY BE COMPRISED OF SPACED PORTIONS NO PART OF WHICH SLOPE INWARDLY TOWARD THE CENTRAL AXIS OF THE CONTAINER, THE EFFECTIVE WIDTH OF EACH PROJECTION FORMING ONE SHOULDER BEING GREATER THAN THE SPACING BETWEEN THE SPACED PROJECTIONS OR PORTIONS OF THE OTHER SHOULDER, THEREBY POSITIVELY LIMITING THE NESTING OF LIKE TELESCOPICALLY ASSOCIATED CONTAINERS.   D R A W I N G

March 20, 1973 R. w. FLETCHER STACKABLE CONTAINERS Filed Aug. 5, 1970 2 Sheets-Sheet 1 March 20, 1973 'R. w. FLETCHER 3,721,367 Q STACKABLE CONTAINERS 2 Sheets-Sheet 2 Filed Aug. 3, 1970 United States Patent 3,721,367 STACKABLE CONTAINERS Robert W. Fletcher, Elk Grove Village, Ill., assignor to Standard Oil Company, Chicago, Ill. Filed Aug. 3, 1970, Ser. No. 60,689 Int. Cl. B6511 21/02 US. Cl. 220-97 C 11 Claims ABSTRACT OF THE DISCLOSURE A stackable container comprising a bottom; a sidewall integral with said bottom tapering upwardly and outwardly from said bottom and terminating in an open upper end; a first circumferential intermittent shoulder in the container sidewall; and a second circumferential intermittent shoulder in the container sidewall, at least one of said shoulders being formed by spaced projections no part of which slope inwardly toward the central axis of the container, the other shoulder may be comprised of spaced portions no part of which slope inwardly toward the central axis of the container, the effective width of each projection forming one shoulder being greater than the spacing between the spaced projections or portions of the other shoulder, thereby positively limiting the nesting of like telescopically associated containers.

BACKGROUND OF THE INVENTION In the manufacture and sale of plastic articles, shipping costs are often a big part of the consumer cost. Shipping costs are higher for a large volume package than for a small volume package. In shipping plastic products, considerable cost savings can be realized if the plastic product can be stacked or positioned so as to occupy a minimum amount of space. Many plastic articles such as tumblers, flower pots, and food containers can only be shipped economically if they are stacked, that is positioned so that one container is telescoped inside another. Previously, plastic containers have had incorporated in their sidewalls a Z-stacking configuration comprising an inner circumferential shoulder having a diameter less than an outer circumferential shoulder positioned axially below the inner shoulder. Such a Z-stacking configuration facilitates stacking since the lower larger diameter shoulder engages the upper smaller diameter shoulder when two like containers are telescopically associated, thereby limiting the nesting (projection of one container inside another) of such containers, and preventing them from becoming impossible to separate. The principal feature of such a Z-stacking configuration, as described in US. Pat. 3,129,213, is an intermediate support means which slopes inwardly toward the containers central axis and is circumferentially continuous in the sidewall of the container. This intermediate support means connects the upper internal shoulder and the lower external shoulder and its axial height determines the depth of nesting of like containers.

Many problems have arisen with such a stacking means. For example, a Z-stacking configuration does not provide for a venting of gases which may be entrapped in the container when attempting to place a cover thereon. Also an intermediate support means which slopes inwardly towards the central axis of the container creates a problem, because of its reverse taper, in removing the die used for container manufacture. The stackable container of this invention overcomes the first mentioned problem of the prior art containers since gases can escape between the intermittent projections forming the shoulders. The stackable container overcomes the second problem of prior art containers since no part of the projections forming the shoulder slope inwardly toward the containers central axis; therefore, there is no reverse taper to impede removal of the die used for container manufacture.

SUMMARY OF THE INVENTION A stackable container comprising a bottom; a sidewall integral with said bottom tapering upwardly and outwardly from said bottom and terminating in an open upper end; a first circumferential intermittent shoulder in the container sidewall; and a second circumferential intermittent shoulder in the container sidewall, at least one of said shoulders being formed by spaced projections no part of which slope inwardly toward the central axis of the container, the other shoulder may be comprised of spaced portions no part of which slope inwardly toward the central axis of the container, the effective width of each projection forming one shoulder being greater than the spacing between the spaced projections or portions of the other shoulder, thereby positively limiting the nesting of like telescopiclly associated containers.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a stackable container of this invention.

FIG. 2 is an enlarged cross-sectional elevational view of the stackable container of FIG. 1 taken along the line 2-2.

FIG. 3 is a partial cross-sectional elevational view of two stackable containers of this invention telescoped one inside the other, one container being slightly rotated in respect to the other.

FIG. 4 is a partial sectional view of two stackable containers of the type shown in FIGS. 1, 2 and 3 taken along the line 4-4 of FIG. 3. The containers are telescoped one inside the other, one container being slightly rotated in respect to the other.

FIG. 5 is a partial elevational view of two stackable containers having an alternative embodiment of the invention of this disclosure telescoped one inside the other. The outer container is shown in cross-section and one container is slightly rotated in respect to the other.

FIG. 6 is a partial elevational cross-sectional view of two stackable containers having the same alternative embodiment shown in FIG. 5, one continer being slightly rotated in respect to the other.

FIG. 7 is an elevational view of a container having another alternative embodiment of the invention of this disclosure.

FIG. 8 is an elevational view of a container having still another alternative embodiment of the invention of this disclosure.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The most preferred embodiment of the invention of this disclosure is shown in FIGS. 1 through 4, where projections 7 and 12 in the container sidewall are triangular in shape. The apexes of triangular shaped projections 7 and 12 are continuous with sidewall 3. Projections 7 and 12 form a dovetail design in container sidewall 3 as seen in FIG. 1. The nesting of the containers, is limited because triangular projections 12 whose bases are directed upwardly toward the mouth of the container and projecting inwardly will engage the bases of triangular projections 7 of a similar container that are directed downwardly toward the bottom of the container and projecting outwardly.

In FIG. 2, bottom 2 of container 1 is connected to sidewall 3, which has incorporated therein a circumferential, intermittent shoulder 6, formed by spaced projections 12 having efiective widths 8. No part of projections 12 slope inwardly toward the central axis 4 of container 1. Spacings 9 between projections 12 are less than eifective widths 13 of projections 7. Sidewall 3 also has incorporated therein a circumferential intermittent shoulder 11, formed by spaced projections 7 no part of which slope inwardly toward the central axis 4 of container 1. Spacings 14 between projections 7 are less than effective widths 8 of projections 12. Most preferred is the case where effective Widths 8 and 13 of projections 7 and 12, respectively, are equal, and greater than spacings 9 and 14. Projections 7 and 12 are comprised of intermittent support sidewalls 16 and 17 respectively. Intermittent support sidewalls 16 and 17 do not slope inwardly toward the central axis 4 of the container, but rather slope outwardly, terminating integrally at support shelves 18 and 19 respectively thus, projections 7 and 12 taper away from central axis 4 of container 1. Intermittent support sidewalls 16 and 17 can be described as having one end integral and continuous with container sidewall 3 and the other integral at support shelves 18 and 19, respectively. Support shelves 18 and 19 project from container sidewall 3 perpendicular to the central axis 4 of container 1 terminating at intermittent support sidewalls 16 and 17, respectievly.

The stacking feature of the invention of this disclosure is shown in greater detail in FIG. 3 where it can be seen that when two containers 1a and 1 are telescopically associated the respective shelves 19 and 18A contact to positively limit the nesting (projection of container 1a into container 1) of such containers. FIG. 4 then shows a sectional view along line 4-4 of FIG. 3. From FIG. 4 it becomes clear that telescopically associated containers may be rotated with respect to each other yet be positively limited from nesting tightly, since effective widths 13 of outward projections 7 are greater than spacings 9 between inward projections 12.

In FIGS. and 6 an alternative emobdiment is shown. Containers 1 and 1a differ from previously described containers in that there are no projections downward corresponding to projections 7, but rather shoulder 11 is comprised of circumferential, intermittent portions in container sidewall 3. These spaced portions are contained in sidewall 3 and are comprised of circumferential intermittent ledges and intermittent sidewall portions 21 and 24, respectively. Circumferential intermittent ledges 21 extend in a plane perpendicular to the central axis of container 1. From FIGS. 5 and 6 it can be seen that intermittent sidewall portions 24 are continuous and flush with intermittent support sidewalls 17, while sections 22 of sidewall 3 remain unchanged. The dotted lines show that segments of projections 12 are now continuous and flush with intermittent sidewall portions 24 of shoulder 11. The nesting of like telescopically associated containers is positively limited by shelf 19 contacting ledge 21 of an upper container. It should be noted that circumferential intermittent ledges 21 must be located within the axial height of projections 12 below point 23 (FIG. 6), which is the point of intersection between a perependicular projection downward from the innermost edge of shoulder 6 and the outside surface of container sidewall 3. In order that circumferential intermittent ledges 21 contact shoulder 6 they must be located above point 25 in container sidewall 3.

Alternatively, it is clear from FIG. 6 that sidewalls 3 of container 1 may extend downward from point 23 parallel to that portion of sidewall 3 above shelf 19 to form an offset in container sidewall 3 as a modification of this alternative embodiment.

Another configuration for the projections described above, rather than the triangles shown in FIGS. 1 through 4, i the teardrop configuration shown in FIG. 7. The effective widths, corresponding to widths 8, and spacings 9 shown in FIGS. 2 and 4 are now measured between the widest points of the teardrop projections. The same would also be true of the effective widths cOrresponding to effective widths 13 and spacings 14 of FIGS. 2 and 4. Spacings 9 are less than effective widths 13 and spacings 14 are less than effective widths 8. As can be seen from FIG. 7 the distance between two such telescopically associated containers will vary depending upon the rotation of one container with respect to the other; therefore, the configuration of FIG. 7 is useful when it is desired that the nesting of telescopically associated containers be limited, yet it is immaterial that the axial distance between the several stacked containers is not the same. In contrast to FIG. 7, however, it is preferred that the projections be of the type where the inner shoulder projections furthermost portions from the central axis are the widest portions thereof and the outer shoulder projections closest portions to the containers central axis are similarly the widest portions thereof. An example is the triangular shaped projections of FIGS. 1 through 4, such projections are alternately arranged in such a manner that the widest portions of the outer shoulder projections are axially below the widest portions of the adjacent inner shoulder projections.

It is clear from FIG. 7 that cone shaped projections could be substituted for the teardrop shaped projections shown therein.

Similarly, an alternate configuration for the projections described above rather than the triangles shown in FIG. 1 through 3, is the trapezoidal configuration shown in FIG. 8. The effective widths corresponding to effective widths 8 and spacings 9 shown in FIGS. 1 and 4 would then be measured between the Widest points of the trapezoidal projections. The same would be true of the effective widths corresponding to widths 13 and 14 of FIGS. 1 and 4. Here again spacings 9 are less than widths 13 and spacings 14 are less than widths 8.

It has been found to be acceptable to locate the projections of the inner and outer shoulders of the invention of this disclosure in working relation anywhere on the container sidewall. In some instances it has been found desirable to dispose the projections immediately adjacent to the open upper end of the container. In some instances the projections in the container sidewall, projecting outwardly from the container sidewall, and the circumferential intermittent shoulder formed thereby, comprises the bottom margin of the container.

As can be readily seen from the drawings, the number of projections circumferentially placed in the container sidewall may vary provided they are changed in size so that the spacing between the projections of the inner shoulder are at, at least one point, less than the effective width of the projections comprising the outer shoulder.

What is claimed is:

1. A stackable container comprising a bottom; a sidewall integral with said bottom tapering upwardly and outwardly from said bottom and terminating in an open upper end; a first circumferential intermittent shoulder in the container sidewall; and a second circumferential intermittent shoulder in the container sidewall, said shoulders being formed by spaced projections no part of which slope inwardly toward the central axis of the container, the effective width of each projection forming one shoulder being greater than the spacing between the spaced projections of the other shoulder, thereby positively limiting the nesting of like telescopically associated containers, said first and second shoulders being further described in that said first shoulder projects inwardly from the container sidewall and said second shoulder projects outwardly from the container sidewall, and said spaced projections forming said first and second shoulders being spaced from each other and one another in the container sidewall and said spaced projections being alternately arranged in such a manner that the widest portions of the outer shoulder projections are located axially below the widest portions of the spaced inner shoulder projections.

2. The container of claim 1 wherein the projections are trapezoidal in shape.

3. The container of claim 1 wherein the projections are triangular in shape.

4. The container of claim 1 wherein said spaced projections in the container sidewall are disposed immediately adjacent to the open upper end of the container.

5. The container of claim 1 wherein the outer shoulder comprises the bottom margin of the container.

6. A stackable container comprising a bottom, a sidewall integral with said bottom, said sidewall tapering upwardly and outwardly from said bottom and terminating in an open upper end; a circumferential intermittent inner shoulder formed by spaced projections in the container sidewall no part of which slope inwardly toward the central axis of the container; and a circumferentially intermittent outer shoulder positioned axially below said inner shoulder formed by spaced projections in the container sidewall no part of which slope inwardly toward the central axis of the container, said projections of said inner and outer shoulders being spaced from one another and each other in the container sidewall, and being of the type where the inner shoulder projections furthermost portions from the central axis are the widest portions thereof and the outer shoulder projections closest portions to the containers central axis are the widest portions thereof, the spacing between said projections of the inner shoulder being less than the effective width of the projections comprising the outer shoulder, said inner shoulder engaging the outer shoulder of a like telescopically associated container thereby positively limiting the nesting of the containers.

7. The stackable container of claim 6 wherein the respective spaced projections comprising the inner shoulder and outer shoulder are comprised of support sidewalls and support shelves said support shelves being perpendicular to the central axis of the container and said support sidewalls sloping outwardly from the central axis of the container, said inner shoulder engaging the outer shoulder of a like telescopically associated container thereby positively limiting the nesting of the containers.

8. The container of claim 6 wherein the projections are teardrop in shape.

9. The container of claim 6 wherein the projections are triangular in shape.

10. The container of claim 6 wherein the projections are trapezoidal in shape.

111. A stackable container comprising a bottom; a sidewall integral with said bottom tapering upwardly and outwardly from said bottom and terminating in an open upper end; a first circumferential intermittent shoulder in the container sidewall; and a second circumferential intermittent shoulder in the container sidewall, said first circumferential intermittent shoulder being formed by spaced projections projecting outwardly from the container sidewall no part of which slope inwardly toward the central axis of the container, and said second circumferential intermittent shoulder being comprised of circumferential projections projecting inwardly from the container sidewall and lying within the axial height of said spaced projections forming said first circumferential intermittent shoulder, said projections comprising said second circumferential intermittent shoulder being further described as having intermittent ledges extending in a plane perpendicular to the central axis of the container, said ledges being circumferentially greater in length than the circumferential distance between the closest points of said spaced projections comprising said first circumferential intermittent shoulder thereby positively limiting the nesting of the like telescopically associated containers.

References Cited UNITED STATES PATENTS 3,353,707 11/1967 Eyles 220-97 C 3,484,018 12/1969 Davis.

FOREIGN PATENTS 976,178 11/1964 Great Britain 22097 C DONALD F. NORTON, Primary Examiner 

